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Role of pulmonary perfusion magnetic resonance imaging for the diagnosis of pulmonary hypertension:A review
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作者 Miriam Lacharie Adriana Villa +3 位作者 Xenios Milidonis Hadeer Hasaneen Amedeo Chiribiri Giulia Benedetti 《World Journal of Radiology》 2023年第9期256-273,共18页
Among five types of pulmonary hypertension,chronic thromboembolic pulmonary hypertension(CTEPH)is the only curable form,but prompt and accurate diagnosis can be challenging.Computed tomography and nuclear medicine-bas... Among five types of pulmonary hypertension,chronic thromboembolic pulmonary hypertension(CTEPH)is the only curable form,but prompt and accurate diagnosis can be challenging.Computed tomography and nuclear medicine-based techniques are standard imaging modalities to non-invasively diagnose CTEPH,however these are limited by radiation exposure,subjective qualitative bias,and lack of cardiac functional assessment.This review aims to assess the methodology,diagnostic accuracy of pulmonary perfusion imaging in the current literature and discuss its advantages,limitations and future research scope. 展开更多
关键词 Pulmonary perfusion MRI Pulmonary hypertension dynamic contrast enhanced magnetic resonance imaging Chronic thromboembolic pulmonary hypertension Computed tomography pulmonary angiography Chronic thromboembolic disease
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Perfusion magnetic resonance imaging of the liver 被引量:15
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作者 Choon Hua Thng Tong San Koh +1 位作者 David J Collins Dow Mu Koh 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第13期1598-1609,共12页
Perfusion magnetic resonance imaging (MRI) studies quantify the microcirculatory status of liver parenchyma and liver lesions, and can be used for the detection of liver metastases, assessing the effectiveness of anti... Perfusion magnetic resonance imaging (MRI) studies quantify the microcirculatory status of liver parenchyma and liver lesions, and can be used for the detection of liver metastases, assessing the effectiveness of antiangiogenic therapy, evaluating tumor viability after anticancer therapy or ablation, and diagnosis of liver cirrhosis and its severity. In this review, we discuss the basic concepts of perfusion MRI using tracer kinetic modeling, the common kinetic models applied for analyses, the MR scanning techniques, methods of data processing, and evidence that supports its use from published clinical and research studies. Technical standardization and further studies will help to establish and validate perfusion MRI as a clinical imaging modality. 展开更多
关键词 magnetic resonance imaging dynamic contrast-enhanced magnetic resonance imaging LIVER Tracer kinetic modeling
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Discrimination of Metastatic from Non-metastatic Mesorectal Lymph Nodes in Rectal Cancer Using Quantitative Dynamic Contrast-Enhanced Magnetic Resonance Imaging 被引量:17
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作者 于小平 文露 +2 位作者 侯静 王晖 卢强 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2016年第4期594-600,共7页
Preoperative detection of lymph nodes(LNs) metastasis is always highly challenging for radiologists nowadays. The utility of quantitative dynamic contrast-enhanced magnetic resonance imaging(QDCE-MRI) in identifyi... Preoperative detection of lymph nodes(LNs) metastasis is always highly challenging for radiologists nowadays. The utility of quantitative dynamic contrast-enhanced magnetic resonance imaging(QDCE-MRI) in identifying LNs metastasis is not well understood. In the present study, 59 patients with histologically proven rectal carcinoma underwent preoperative QDCE-MRI. The short axis diameter ratio, long axis diameter ratio, short-to-long axis diameter ratio and QDEC-MRI parameters(Ktrans, Kep, fPV and Ve) values were compared between the non-metastatic(n=44) and metastatic(n=35) LNs groups based on pathological examination. Compared with the non-metastatic group, the metastatic group exhibited significantly higher short axis diameter(7.558±0.668 mm vs. 5.427±0.285 mm), Ktrans(0.483±0.198 min-1 vs. 0.218±0.116 min^-1) and Ve(0.399±0.118 vs. 0.203±0.096) values(all P〈0.05). The short-to-long axis diameter ratio, long axis diameter ratio, Kep and fPV values did not show significant differences between the two groups. In conclusion, our results showed that for LNs larger than 5 mm in rectal cancer, there are distinctive differences in the Ktrans and Ve values between the metastatic and non-metastatic LNs, suggesting that QDCE-MRI may be potentially helpful in identifying LNs status. 展开更多
关键词 rectal cancer lymph node dynamic contrast-enhanced magnetic resonance imaging quantitative analysis sensitivity and specificity
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Dual-input two-compartment pharmacokinetic model of dynamic contrast-enhanced magnetic resonance imaging in hepatocellular carcinoma 被引量:4
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作者 Jian-Feng Yang Zhen-Hua Zhao +6 位作者 Yu Zhang Li Zhao Li-Ming Yang Min-Ming Zhang Bo-Yin Wang Ting Wang Bao-Chun Lu 《World Journal of Gastroenterology》 SCIE CAS 2016年第13期3652-3662,共11页
AIM: To investigate the feasibility of a dual-input two-compartment tracer kinetic model for evaluating tumorous microvascular properties in advanced hepatocellular carcinoma(HCC). METHODS: From January 2014 to April ... AIM: To investigate the feasibility of a dual-input two-compartment tracer kinetic model for evaluating tumorous microvascular properties in advanced hepatocellular carcinoma(HCC). METHODS: From January 2014 to April 2015, we prospectively measured and analyzed pharmacokinetic parameters [transfer constant(K_(trans)), plasma flow(F_p), permeability surface area product(PS), efflux rate constant(k_(ep)), extravascular extracellular space volume ratio(V_e), blood plasma volume ratio(V_p), and hepatic perfusion index(HPI)] using dual-input two-compartment tracer kinetic models [a dual-input extended Tofts model and a dual-input 2-compartment exchange model(2CXM)] in 28 consecutive HCC patients. A well-known consensus that HCC is a hypervascular tumor supplied by the hepatic artery and the portal vein was used as a reference standard. A paired Student's t-test and a nonparametric paired Wilcoxon rank sum test were used to compare the equivalent pharmacokinetic parameters derived from the two models, and Pearson correlation analysis was also applied to observe the correlations among all equivalent parameters. The tumor size and pharmacokinetic parameters were tested by Pearson correlation analysis, while correlations among stage, tumor size and all pharmacokinetic parameters were assessed by Spearman correlation analysis. RESULTS: The F_p value was greater than the PS value(F_P = 1.07 m L/m L per minute, PS = 0.19 m L/m L per minute) in the dual-input 2CXM; HPI was 0.66 and 0.63 in the dual-input extended Tofts model and the dualinput 2CXM, respectively. There were no significant differences in the K_(ep), V_p, or HPI between the dual-input extended Tofts model and the dual-input 2CXM(P = 0.524, 0.569, and 0.622, respectively). All equivalent pharmacokinetic parameters, except for V_e, were correlated in the two dual-input two-compartment pharmacokinetic models; both Fp and PS in the dualinput 2CXM were correlated with K_(trans) derived from the dual-input extended Tofts model(P = 0.002, r = 0.566; P = 0.002, r = 0.570); K_(ep), V_p, and HPI between the two kinetic models were positively correlated(P = 0.001, r = 0.594; P = 0.0001, r = 0.686; P = 0.04, r = 0.391, respectively). In the dual input extended Tofts model, V_e was significantly less than that in the dual input 2CXM(P = 0.004), and no significant correlation was seen between the two tracer kinetic models(P = 0.156, r = 0.276). Neither tumor size nor tumor stage was significantly correlated with any of the pharmacokinetic parameters obtained from the two models(P > 0.05).CONCLUSION: A dual-input two-compartment pharmacokinetic model(a dual-input extended Tofts model and a dual-input 2CXM) can be used in assessing the microvascular physiopathological properties before the treatment of advanced HCC. The dual-input extended Tofts model may be more stable in measuring the V_e; however, the dual-input 2CXM may be more detailed and accurate in measuring microvascular permeability. 展开更多
关键词 HEPATOCELLULAR CARCINOMA dynamic contrastenhanced magnetic resonance imaging PHARMACOKINETICS
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Erythropoietin reduces apoptosis of brain tissue cells in rats after cerebral ischemia/reperfusion injury:a characteristic analysis using magnetic resonance imaging 被引量:14
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作者 Chun-juan Jiang Zhong-juan Wang +3 位作者 Yan-jun Zhao Zhui-yang Zhang Jing-jing Tao Jian-yong Ma 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第9期1450-1455,共6页
Some in vitro experiments have shown that erythropoietin (EPO) increases resistance to apoptosis and facilitates neuronal survival follow- ing cerebral ischemia. However, results from in vivo studies are rarely repo... Some in vitro experiments have shown that erythropoietin (EPO) increases resistance to apoptosis and facilitates neuronal survival follow- ing cerebral ischemia. However, results from in vivo studies are rarely reported. Perfusion-weighted imaging (PWI) and diffusion-weighted imaging (DWI) have been applied successfully to distinguish acute cerebral ischemic necrosis and penumbra in living animals; therefore, we hypothesized that PWI and DWI could be used to provide imaging evidence in vivo for the conclusion that EPO could reduce apoptosis in brain areas injured by cerebral ischemia/reperfusion. To validate this hypothesis, we established a rat model of focal cerebral ischemia/ reperfusion injury, and treated with intra-cerebroventricular injection of EPO (5,000 U/kg) 20 minutes before injury. Brain tissue in the ischemic injury zone was sampled using MRI-guided localization. The relative area of abnormal tissue, changes in PWI and DWI in the ischemic injury zone, and the number of apoptotic cells based on TdT-mediated dUTP-biotin nick end-labeling (TUNEL) were assessed. Our findings demonstrate that EPO reduces the relative area of abnormally high signal in PWI and DWI, increases cerebral blood volume, and decreases the number of apoptotic cells positive for TUNEL in the area injured by cerebral ischemia/reperfusion. The experiment pro- vides imaging evidence in vivo for EPO treating cerebral ischemia/reperfusion injury. 展开更多
关键词 nerve regeneration nerve protection cerebral ischemia/reperfusion ERYTHROPOIETIN magnetic resonance imaging diffusion-weightedimaging apparent diffusion coefficient perfusion-weighted imaging cerebral blood volume mean transit time APOPTOSIS neural regeneration
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Dynamic contrast-enhanced magnetic resonance imaging of prostate cancer: A review of current methods and applications 被引量:8
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作者 Yousef Mazaheri Oguz Akin Hedvig Hricak 《World Journal of Radiology》 CAS 2017年第12期416-425,共10页
In many areas of oncology, dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI) has proven to be a clinically useful, non-invasive functional imaging technique to quantify tumor vasculature and tumor perfusio... In many areas of oncology, dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI) has proven to be a clinically useful, non-invasive functional imaging technique to quantify tumor vasculature and tumor perfusion characteristics. Tumor angiogenesis is an essential process for tumor growth, proliferation, and metastasis. Malignant lesions demonstrate rapid extravasation of contrast from the intravascular space to the capillary bed due to leaky capillaries associated with tumor neovascularity. DCE-MRI has the potential to provide information regarding blood flow, areas of hypoperfusion, and variations in endothelial permeability and microvessel density to aid treatment selection, enable frequent monitoring during treatment and assess response to targeted therapy following treatment. This review will discuss the current status of DCE-MRI in cancer imaging, with a focus on its use in imaging prostate malignancies as well as weaknesses that limit its widespread clinical use. The latest techniques for quantification of DCE-MRI parameters will be reviewed and compared. 展开更多
关键词 Prostate cancer Prostate magnetic resonance imaging Tumor angiogenesis dynamic contrast-enhanced magnetic resonance imaging Kep = rate constant between extracellular extravascular space and plasma space Ktrans = volume transfer constant
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Mammography combined with breast dynamic contrast-enhanced-magnetic resonance imaging for the diagnosis of early breast cancer 被引量:4
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作者 Yakun He Guohui Xu +4 位作者 Jin Ren Bin Feng Xiaolei Dong Hao Lu Changjiu He 《Oncology and Translational Medicine》 2016年第4期165-168,共4页
Objective The aim of this study was to investigate the application of mammography combined with breast dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI) for the diagnosis of early breast cancer. Methods Ma... Objective The aim of this study was to investigate the application of mammography combined with breast dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI) for the diagnosis of early breast cancer. Methods Mammography and DCE-MRI were performed for 120 patients with breast cancer(malignant, 102; benign; 18). Results The sensitivity of mammography for early diagnosis of breast cancer was 66.67%, specificity was 77.78%, and accuracy was 68.33%. The sensitivity of MRI for early diagnosis of breast cancer was 94.12%, specificity was 88.89%, and accuracy was 93.33%. However, the sensitivity of mammography combined with DCE-MRI volume imaging with enhanced water signal(VIEWS) scanning for early diagnosis of breast cancer was 97.06%, specificity was 94.44%, and accuracy was 96.67%. Conclusion Mammography combined with DCE-MRI increased the sensitivity, specificity, and accuracy of diagnosing early breast cancer. 展开更多
关键词 breast carcinoma mammography nuclear magnetic resonance dynamic enhancement time signal curve
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Prediction of radiosensitivity in primary central nervous system germ cell tumors using dynamic contrast-enhanced magnetic resonance imaging 被引量:3
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作者 Chenlu Feng Peiyi Gao +4 位作者 Xiaoguang Qiu Tianyi Qian Yan Lin Jian Zhou Binbin Sui 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2015年第3期231-238,共8页
Objective: To evaluate the feasibility of dynamic contrast-enhanced magnetic resonance imaging(DCEMRI) for predicting tumor response to radiotherapy in patients with suspected primary central nervous system(CNS) ... Objective: To evaluate the feasibility of dynamic contrast-enhanced magnetic resonance imaging(DCEMRI) for predicting tumor response to radiotherapy in patients with suspected primary central nervous system(CNS) germ cell tumors(GCTs).Methods: DCE-MRI parameters of 35 patients with suspected primary CNS GCTs were obtained prior to diagnostic radiation, using the Tofts and Kermode model. Radiosensitivity was determined in tumors diagnosed 2 weeks after radiation by observing changes in tumor size and markers as a response to MRI. Taking radiosensitivity as the gold standard, the cut-off value of DCE-MRI parameters was measured by receiver operating characteristic(ROC) curve. Diagnostic accuracy of DCE-MRI parameters for predicting radiosensitivity was evaluated by ROC curve.Results: A significant elevation in transfer constant(K^trans) and extravascular extracellular space(Ve)(P=0.000), as well as a significant reduction in rate constant(Kep)(P=0.000) was observed in tumors. K^trans, relative K^trans, and relative Kep of the responsive group were significantly higher than non-responsive groups. No significant difference was found in Kep, Ve, and relative Ve between the two groups. Relative K^trans showed the best diagnostic value in predicting radiosensitivity with a sensitivity of 100%, specificity of 91.7%, positive predictive value(PPV) of 95.8%, and negative predictive value(NPV) of 100%.Conclusions: Relative K^trans appeared promising in predicting tumor response to radiation therapy(RT). It is implied that DCE-MRI pre-treatment is a requisite step in diagnostic procedures and a novel and reliable approach to guide clinical choice of RT. 展开更多
关键词 dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) extravascular extracellular space germ cell tumors (GCTs) RADIOSENSITIVITY rate constant transfer constant
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Evaluation of tumor response to antiangiogenic therapy in patients with recurrent gliomas using contrast-enhanced perfusion-weighted magnetic resonance imaging techniques:A meta-analysis 被引量:1
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作者 Akanganyira Kasenene Aju Baidya +1 位作者 Salman Shams Hai-Bo Xu 《World Journal of Meta-Analysis》 2019年第2期51-65,共15页
BACKGROUND It is of vital importance to find radiologic biomarkers that can accurately predict treatment response. Usually, the initiation of antiangiogenic therapy causes a rapid decrease in the contrast enhancing tu... BACKGROUND It is of vital importance to find radiologic biomarkers that can accurately predict treatment response. Usually, the initiation of antiangiogenic therapy causes a rapid decrease in the contrast enhancing tumor. However, the treatment response is observed only in a fraction of patients due to the partial radiological response secondary to stabilization of abnormal vessels which does not essentially indicate a true antitumor effect. Perfusion-weighted magnetic resonance imaging(PWMRI) techniques have shown implicitness as a strong imaging biomarker for gliomas since they give hemodynamic information of blood vessels. Hence, there is a rapid expansion of PW-MRI related studies and clinical applications.AIM To determine the diagnostic performance of PW-MRI techniques including:(A)dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI); and(B)dynamic susceptibility contrast magnetic resonance imaging(DSC-MRI) for evaluating response to antiangiogenic therapy in patients with recurrent gliomas.METHODS Databases such as PubMed(MEDLINE included), EMBASE, and Google Scholar were searched for relevant original articles. The included studies were assessed for methodological quality with the Quality Assessment of Diagnostic Accuracy Studies 2 tool. Medical imaging follow-up or histopathological analysis was used as the reference standard. The data were extracted by two reviewers independently, and then the sensitivity, specificity, summary receiver operating characteristic curve, area under the curve(AUC), and heterogeneity were calculated using Meta-Disc 1.4 software.RESULTS This study analyzed a total of six articles. The overall sensitivity for DCE-MRI and DSC-MRI was 0.69 [95% confidence interval(CI): 0.53-0.82], and the specificity was 0.99(95%CI: 0.93-1) by a random effects model(DerSimonianeeLaird model). The likelihood ratio(LR) +, LR-, and diagnostic odds ratio(DOR)were 12.84(4.54-36.28), 0.35(0.22-0.53), and 24.44(7.19-83.06), respectively. The AUC(± SE) was 0.9921(± 0.0120), and the Q* index(± SE) was 0.9640(± 0.0323).For DSC-MRI, the sensitivity was 0.73, the specificity was 0.98, the LR+ was 7.82,the LR-was 0.32, the DOR was 31.65, the AUC(± SE) was 0.9925(± 0.0132), and the Q* index was 0.9649(± 0.0363). For DCE-MRI, the sensitivity was 0.41, the specificity was 0.97, the LR+ was 5.34, the LR-was 0.71, the DOR was 8.76, the AUC(± SE) was 0.9922(± 0.2218), and the Q* index was 0.8935(± 0.3037).CONCLUSION This meta-analysis demonstrated a beneficial value of PW-MRI(DSC-MRI and DCE-MRI) in monitoring the response of recurrent gliomas to antiangiogenic therapy, with reasonable sensitivity, specificity, +LR, and-LR. 展开更多
关键词 Glioma perfusion-weighted magnetic resonance IMAGING dynamic contrastenhanced magnetic resonance IMAGING dynamic susceptibility contrast magnetic resonance IMAGING Anti-vascular endothelial growth factor ANTIANGIOGENIC Metaanalysis
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Changes in cerebral perfusion detected by dynamic susceptibility contrast magnetic resonance imaging: normal volunteers examined during normal breathing and hyperventilation
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作者 Ronnie Wirestam Christian Engvall +3 位作者 Erik Ryding Stig Holtas Freddy Stahlberg Peter Reinstrup 《Journal of Biomedical Science and Engineering》 2009年第4期210-215,共6页
Global cerebral perfusion parameters were measured using dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) in eight healthy volunteers examined during normal breathing and spontaneous hyperventilati... Global cerebral perfusion parameters were measured using dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) in eight healthy volunteers examined during normal breathing and spontaneous hyperventilation. DSC-MRI-based cerebral blood flow (CBF) de-creased during hyperventilation in all volun-teers (average decrease 29%), and the corre-sponding global CBF estimates were 73±19ml/ (min100g) during normal breathing and 52± 7.9ml/(min100g) during hyperventilation (mean ±SD, n=8). Furthermore, the hypocapnic condi-tions induced by hyperventilation resulted in a prolongation of the global mean transit time (MTT) by on average 14%. The observed CBF estimates appeared to be systematically over-estimated, in accordance with previously pub-lished DSC-MRI results, but reduced to more reasonable levels when a previously retrieved calibration factor was applied. 展开更多
关键词 magnetic resonance Imaging perfusion CEREBRAL blood Flow Mean TRANSIT Time Hypocapnia
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Intraoperative perfusion magnetic resonance imaging: Cutting-edge improvement in neurosurgical procedures 被引量:3
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作者 Stephan Ulmer 《World Journal of Radiology》 CAS 2014年第8期538-543,共6页
The goal in brain tumor surgery is to remove the maxi-mum achievable amount of the tumor, preventing damage to "eloquent" brain regions as the amount of brain tumor resection is one of the prognostic factors... The goal in brain tumor surgery is to remove the maxi-mum achievable amount of the tumor, preventing damage to "eloquent" brain regions as the amount of brain tumor resection is one of the prognostic factors for time to tumor progression and median survival. To achieve this goal, a variety of technical advances have been in-troduced, including an operating microscope in the late 1950 s, computer-assisted devices for surgical navigation and more recently, intraoperative imaging to incorporate and correct for brain shift during the resection of the lesion. However, surgically induced contrast enhancement along the rim of the resection cavity hampers interpretation of these intraoperatively acquired magnetic resonance images. To overcome this uncertainty, perfusion techniques [dynamic contrast enhanced magnetic resonance imaging(DCE-MRI), dynamic susceptibility contrast magnetic resonance imaging(DSC-MRI)] have been introduced that can differentiate residual tumor from surgically induced changes at the rim of the resec-tion cavity and thus overcome this remaining uncer-tainty of intraoperative MRI in high grade brain tumor resection. 展开更多
关键词 INTRAOPERATIVE magnetic resonance IMAGING dynamic susceptibility CONTRAST magnetic resonance IMAGING dynamic CONTRAST enhanced magnetic resonance IMAGING Surgically induced CONTRAST enhancement Neurosurgery
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Clinical applications of advanced magnetic resonance imaging techniques for arthritis evaluation 被引量:3
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作者 Teodoro Martín Noguerol Antonio Luna +1 位作者 Marta Gómez Cabrera Alexie D Riofrio 《World Journal of Orthopedics》 2017年第9期660-673,共14页
Magnetic resonance imaging(MRI) has allowed a comprehensive evaluation of articular disease, increasing the detection of early cartilage involvement, bone erosions, and edema in soft tissue and bone marrow compared to... Magnetic resonance imaging(MRI) has allowed a comprehensive evaluation of articular disease, increasing the detection of early cartilage involvement, bone erosions, and edema in soft tissue and bone marrow compared to other imaging techniques. In the era of functional imaging, new advanced MRI sequences are being successfully applied for articular evaluation in cases of inflammatory, infectious, and degenerative arthropathies. Diffusion weighted imaging, new fat suppression techniques such as DIXON, dynamic contrast enhanced-MRI, and specific T2 mapping cartilage sequences allow a better understanding of the physiopathological processes that underlie these different arthropathies. They provide valuable quantitative information that aids in their differentiation and can be used as potential biomarkers of articular disease course and treatment response. 展开更多
关键词 magnetic resonance IMAGING Joint Diffusion weighted IMAGING dynamic contrast enhanced MUSCULOSKELETAL system CARTILAGE DIXON ARTHRITIS
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Enhancement patterns of small hepatocellular carcinoma shown by dynamic MRI and CT 被引量:1
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作者 Fu-Hua Yan Ji-Zhang Shen +6 位作者 Ren-Chen Li Meng-Su Zeng Dong Wu Kang-Rong Zhou Jun Yang Jing-Shan Gong Wei-Bin Shi the Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai 200032, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2002年第3期420-424,共5页
Objectives: To study prospectively the enhancement features of small hepatocellular carcinoma (SHCC) with multi-phase scanning of dynamic MRI and spi- ral CT, and discuss the superiority of dynamic MRI to spiral CT. M... Objectives: To study prospectively the enhancement features of small hepatocellular carcinoma (SHCC) with multi-phase scanning of dynamic MRI and spi- ral CT, and discuss the superiority of dynamic MRI to spiral CT. Methods: Multi-phase dynamic contrast scanning of high field MRI and spiral CT were performed in 53 patients with SHCC. The arterial phase, portal ve- nous phase and delayed phase scanning of spiral CT was done after the pre-contrast scanning of the entire liver. MRI was performed with SE sequence and fast multiplanar spoiled gradient-recalled sequence dy- namic multi-phase contrast scanning. Results: Seventy-six lesions were found in all 53 pa- tients. Sixty-nine and 54 of the 76 lesions enhanced obviously in MRI and spiral CT arterial phase scan- ning respectively. The typical enhancement patterns of SHCC in the arterial phase, portal venous phase and delayed phase scanning of MRI and spiral CT were hyper-hypo-hypointense (dense) and hyper-iso- hypointense (dense). Atypical enhancement patterns were hyper-hyper-hyperintense (dense), hyper-iso- isointense (dense) and hypo-hypo-hypointense (dense). Conclusions: Both MRI and spiral CT multi-phase dynamic contrast-enhanced scanning could demon- strate the enhancement features of SHCC, and arte- rial phase scan of MRI was superior to spiral CT in reflecting the hypervascular characterization of SHCC. In addition, MRI was better than spiral CT in characterization of hepatic lesions combined with SE sequence. 展开更多
关键词 magnetic resonance imaging computed tomography LIVER NEOPLASMS dynamic enhancement
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Texture analysis on parametric maps derived from dynamic contrast-enhanced magnetic resonance imaging in head and neck cancer 被引量:6
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作者 Jacobus FA Jansen Yonggang Lu +5 位作者 Gaorav Gupta Nancy Y Lee Hilda E Stambuk Yousef Mazaheri Joseph O Deasy Amita Shukla-Dave 《World Journal of Radiology》 CAS 2016年第1期90-97,共8页
AIM: To investigate the merits of texture analysis on parametric maps derived from pharmacokinetic modeling with dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI) as imaging biomarkers for the prediction o... AIM: To investigate the merits of texture analysis on parametric maps derived from pharmacokinetic modeling with dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI) as imaging biomarkers for the prediction of treatment response in patients with head and neck squamous cell carcinoma(HNSCC). METHODS: In this retrospective study,19 HNSCC patients underwent pre- and intra-treatment DCEMRI scans at a 1.5T MRI scanner. All patients had chemo-radiation treatment. Pharmacokinetic modeling was performed on the acquired DCE-MRI images,generating maps of volume transfer rate(Ktrans) and volume fraction of the extravascular extracellular space(ve). Image texture analysis was then employed on maps of Ktrans and ve,generating two texture measures: Energy(E) and homogeneity.RESULTS: No significant changes were found for the mean and standard deviation for Ktrans and ve between pre- and intra-treatment(P > 0.09). Texture analysis revealed that the imaging biomarker E of ve was significantly higher in intra-treatment scans,relative to pretreatment scans(P < 0.04). CONCLUSION: Chemo-radiation treatment in HNSCC significantly reduces the heterogeneity of tumors. 展开更多
关键词 Tumor HETEROGENEITY dynamic contrastenhanced magnetic resonance imaging Image texture analysis Head and NECK SQUAMOUS cell CARCINOMAS
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Magnetic resonance imaging-guided focused ultrasound to increase localized blood-spinal cord barrier permeability 被引量:1
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作者 Allison H.Payne Gregory W.Hawryluk +6 位作者 Yoshimi Anzai Henrik Odéen Megan A.Ostlie Ethan C.Reichert Amanda J.Stump Satoshi Minoshima Donna J.Cross 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第12期2045-2049,共5页
Spinal cord injury(SCI) affects thousands of people every year in the USA, and most patients are left with some permanent paralysis. Therapeutic options are limited and only modestly affect outcome. To address this ... Spinal cord injury(SCI) affects thousands of people every year in the USA, and most patients are left with some permanent paralysis. Therapeutic options are limited and only modestly affect outcome. To address this issue, we used magnetic resonance imaging-guided focused ultrasound(MRg FUS) as a non-invasive approach to increase permeability in the blood-spinal cord barrier(BSCB). We hypothesize that localized, controlled sonoporation of the BSCB by MRg FUS will aid delivery of therapeutics to the injury. Here, we report our preliminary findings for the ability of MRg FUS to increase BSCB permeability in the thoracic spinal cord of a normal rat model. First, an excised portion of normal rat spinal column was used to characterize the acoustic field and to estimate the insertion losses that could be expected in an MRg FUS blood spinal cord barrier opening. Then, in normal rats, MRg FUS was applied in combination with intravenously administered microbubbles to the spinal cord region. Permeability of the BSCB was indicated as signal enhancement by contrast administered prior to T1-weighted magnetic resonance imaging and verified by Evans blue dye. Neurological testing using the Basso, Beattie, and Breshnahan scale and the ladder walk was normal in 8 of 10 rats tested. Two rats showed minor impairment indicating need for further refinement of parameters. No gross tissue damage was evident by histology. In this study, we have opened successfully the blood spinal cord barrier in the thoracic region of the normal rat spine using magnetic resonance-guided focused ultrasound combined with microbubbles. 展开更多
关键词 focused ultrasound spinal cord magnetic resonance imaging CONTRAST-ENHANCED blood-spinalcord barrier
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Diagnostic value of DWI combined with dynamic contrast-enhanced scan of cervical cancer staging弥散加权成像结合动态增强扫描在宫颈癌分期中的诊断价值 被引量:4
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作者 纪昌焕 黄健威 +1 位作者 杨海南 陈绵荣 《中国医药导报》 CAS 2015年第25期124-128,共5页
目的探讨磁共振弥散加权成像(DWI)结合动态增强扫描在子宫颈癌分期中的诊断价值。方法回顾性分析2013年11月-2014年8月广州医科大学附属第四医院56例经病理证实的宫颈癌患者的DWI及动态增强扫描结果。测量病灶表观扩散系数(ADC)值... 目的探讨磁共振弥散加权成像(DWI)结合动态增强扫描在子宫颈癌分期中的诊断价值。方法回顾性分析2013年11月-2014年8月广州医科大学附属第四医院56例经病理证实的宫颈癌患者的DWI及动态增强扫描结果。测量病灶表观扩散系数(ADC)值判断浸润范围,并与手术病理结果进行比较。结果宫颈癌在DWI图像上表现为高信号,ADC值降低,平均ADC值为(0.92±0.16)×10^-3mm^2/s。动态增强扫描早期病灶明显快速强化,延迟期病灶中心呈低信号,病灶边缘呈稍高信号,与邻近正常宫颈组织信号明显不同,形成对比。DWI结合动态增强扫描对宫颈癌FIGO分期(2009)总准确性为93.75%,高于常规MRI分期总准确性(81.25%),对宫旁浸润评估的准确性为100.00%。结论,DWI结合动态增强扫描磁共振检查能提高宫颈癌侵犯程度评价的准确性,对宫颈癌的诊断、临床分期及制订正确的治疗方案具有重要意义。 展开更多
关键词 磁共振成像 扩散加权成像 动态增强 宫颈癌 肿瘤分期
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Abnormal characterization of dynamic functional connectivity in Alzheimer’s disease 被引量:8
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作者 Cui Zhao Wei-Jie Huang +7 位作者 Feng Feng Bo Zhou Hong-Xiang Yao Yan-E Guo Pan Wang Lu-Ning Wang Ni Shu Xi Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第9期2014-2021,共8页
Numerous studies have shown abnormal brain functional connectivity in individuals with Alzheimer’s disease(AD)or amnestic mild cognitive impairment(aMCI).However,most studies examined traditional resting state functi... Numerous studies have shown abnormal brain functional connectivity in individuals with Alzheimer’s disease(AD)or amnestic mild cognitive impairment(aMCI).However,most studies examined traditional resting state functional connections,ignoring the instantaneous connection mode of the whole brain.In this case-control study,we used a new method called dynamic functional connectivity(DFC)to look for abnormalities in patients with AD and aMCI.We calculated dynamic functional connectivity strength from functional magnetic resonance imaging data for each participant,and then used a support vector machine to classify AD patients and normal controls.Finally,we highlighted brain regions and brain networks that made the largest contributions to the classification.We found differences in dynamic function connectivity strength in the left precuneus,default mode network,and dorsal attention network among normal controls,aMCI patients,and AD patients.These abnormalities are potential imaging markers for the early diagnosis of AD. 展开更多
关键词 Alzheimer’s disease amnestic mild cognitive impairment blood oxygen level-dependent default mode network dynamic functional connectivity frontoparietal network resting-state functional magnetic resonance imaging support vector machine
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Diagnosis value of diffusion-weighted MR imaging with dynamic enhanced scanning toward pancreatic endocrine tumors 被引量:1
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作者 Xingrong Hu Xiannian Cui +1 位作者 Jun Chen Biyong Tan 《The Chinese-German Journal of Clinical Oncology》 CAS 2014年第1期14-18,共5页
Objective: The aim of our study was to analysis the pictures of conventional magnetic resonance imaging (MR), diffusion-weighted imaging (DWl) and dynamic enhanced magnetic resonance imaging (DEMRI) of pancreat... Objective: The aim of our study was to analysis the pictures of conventional magnetic resonance imaging (MR), diffusion-weighted imaging (DWl) and dynamic enhanced magnetic resonance imaging (DEMRI) of pancreatic endocrine tumors (PETs), and evaluate diagnostic value of MR, DWl and DEMRI for diagnosing PETs. Methods: DWl and DEMRI scanning toward 13 patients with PETs being confirmed by surgical pathology before surgery on the basis of conventional MR scanning were carried out, and MR findings was analyzed retrospectively. Results: Of 13 patients with PETs there was 11 cases with single lesion, 2 with multiple, and had 15 lesions altogether, of which there were 3 lesions in pancreatic head, 1 in its neck, 2 in its body, 4 in its body and tail, 5 in its tail. MR findings: (1) T1WI signal was low or slightly lower (9/15), and equal ones (5/15); (2) T2WI showed high or slightly higher signal (10/15), and equal ones (5/15); (3) T1WI with fat suppression: the signal was low (11/15), mixed signal (2/15), and equal ones (2/15); (4) DWI: normal pancreatic tissue exhibited homogeneous intermediate signal, all 15 lesions were high or slightly higher signal, the measured ADC values of tissue of PETs was (1.124 ± 0.252) × 104 mm2/s, and the ADC value of normal pancreatic tissue (1.873 ± 0.157) × 10^3 mm2/s; (5) Enhanced (M3D/LAVA) scanning: among 13 patients with PETs there were 12 pancreatic lesions with significantly enhanced signals in the arterial phase in all 15, and significantly higher than normal pancreatic tissue, and two slight enhancement was slightly higher signal; and 1 no enhancement. Enhanced pattern: homogeneous enhancement were 6 lesions, and the heterogeneous 4, and the edge ring 5. Conclusion: MR and DWl combining with DEMRI help qualitative diagnosis of pancreatic endocrine tumors. 展开更多
关键词 PANCREAS endocrine tumors magnetic resonance imaging diffusion-weighted imaging dynamic enhancement
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BLOOD FLOW PATTERN AND QUANTITATIVE STUDY IN SOLITARY PULMONARY NODULES WITH DYNAMIC CONTRAST-ENHANCED MRI 被引量:1
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作者 杨春山 肖湘生 +3 位作者 刘士远 李慎江 李惠民 李成洲 《Journal of Shanghai Second Medical University(Foreign Language Edition)》 2007年第1期41-45,57,共6页
Objective To evaluate the efficacy of contrast enhanced dynamic MRI in differentiating solitary pulmonary nodules(SPNs). Methods Eighty-three patients with SPNs undertaken contrast enhanced dynamic MRI. Time-signal ... Objective To evaluate the efficacy of contrast enhanced dynamic MRI in differentiating solitary pulmonary nodules(SPNs). Methods Eighty-three patients with SPNs undertaken contrast enhanced dynamic MRI. Time-signal intensity curve (T-SI Curve) was made. Peak height (PH) , steepest slope (SS), maximum enhancement ( Emax ) and the enhancement rates of signal intensity were recorded at the frst ( E1 ), second ( E2 ), third ( E3 ) , fourth ( E4 ) , fifth (E5), and sixth ( E6 ) minute after injection. Results Malignant nodules and inflammatory nodules enhanced significantly higher than benign nodules, and malignant nodules and inflammatory nodules showed obviously higher PH, SS, Emax, El-E6 values than benign nodules ( P 〈 0. 01 ). There were no sig- nificant differences in PH, SS, Emax, E1-E6 values between malignant nodules and inflammatory nodules (P 〉 0. 05). Conclusion Contrast enhanced dynamic MR imaging can provide SPNs' hemodynamic information and is helpful in differentiating SPNs. 展开更多
关键词 solitary pulmonary nodules magnetic resonance imaging dynamic enhancement
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动态增强MRI定量参数及肿瘤标记物对乳腺癌新辅助化疗疗效的评估价值分析 被引量:2
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作者 马瑞 王彦辉 +3 位作者 杜敏 齐先龙 张琳 王唯伟 《中国医学装备》 2024年第1期73-77,共5页
目的:探索动态增强磁共振成像(DCE-MRI)定量参数及肿瘤标记物对乳腺癌新辅助化疗疗效的评估价值。方法:选取2019年5月至2022年5月在济宁市第一人民医院接受新辅助化疗联合手术干预的75例乳腺癌患者,根据实体瘤疗效评价标准(RECIST)将其... 目的:探索动态增强磁共振成像(DCE-MRI)定量参数及肿瘤标记物对乳腺癌新辅助化疗疗效的评估价值。方法:选取2019年5月至2022年5月在济宁市第一人民医院接受新辅助化疗联合手术干预的75例乳腺癌患者,根据实体瘤疗效评价标准(RECIST)将其分为有效组(54例)和无效组(21例),比较化疗前和化疗后两组患者DCE-MRI定量参数血管外细胞外间隙容积比(V_(e))、速率常数(K_(ep))及容积转换常数(K^(trans))指标与肿瘤标志物癌胚抗原(CEA)、糖类抗原(CA125)及糖类抗原15-3(CA15-3)水平,采用受试者工作特征(ROC)曲线分析各项诊断方式预测效能。结果:化疗后,有效组患者DCEMRI定量参数Ve、K_(ep)及K^(trans)与无效组比较,差异有统计学意义(t=7.237、51.695、16.879,P<0.05)。有效组患者肿瘤标志物CEA、CA125及CA15-3与无效组比较,差异有统计学意义(t=44.201、6.736、6.885,P<0.05)。V_(e)、K_(ep)、K^(trans)、CEA、CA125及CA15-3的6项指标联合预测乳腺癌新辅助化疗疗效ROC曲线下面积(AUC)值为0.979,显著高于各项指标单独检测的AUC值,差异有统计学意义(Z=2.993、2.679、2.510、2.731、3.215、3.071,P<0.05)。结论:肿瘤标记物联合DCE-MRI定量参数可更好预测乳腺癌新辅助化疗疗效情况,间接评估预后。 展开更多
关键词 动态增强磁共振成像(DCE-MRI) 肿瘤标记物 化疗 乳腺癌
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